1. Field of the Invention
The present invention relates to machines for making ice-cream or whipped cream in a short time (so-called "espresso" machines) and concerns a device for improving the storage conditions of the food mixture in the machine and at the outlet holes of the delivery tap.
2. Description of the Prior Art
Generally, in the whipped cream and espresso ice-cream machines, the food mixture is stored in the liquid state in proper refrigerated containers or in reservoirs inside a refrigerated cell.
In both cases, the mixture is protected from the external environment by lids (in the case of refrigerated containers) or doors (in the case of the refrigerated cell).
In spite of this protection, the exposed surface of the mixture in the container or in the reservoir is in contact with the air trapped under the lid or in the refrigerated cell. This air from the external environment could be polluted and contaminate the mixture leading to an increase in the quantity of bacteria in the mixture itself. In such a case, all the effort to store the mixture under optimum hygenic conditions, i.e. scrupulous cleaning of the machine, loading with pasteurized product and rigorous control of the storage temperature, would all be in vain.
Further, these machines have delivery taps for the product mounted externally on the machine, easily accessible to the user. Such a delivery tap is connected to the whipping cylinder the whipped cream or to the mixing cylinder of the espresso ice-cream machine, and, after the first delivery, always remains in contact with the product, so that after every delivery some product in the area of said delivery tap remains in contact with the outside environment.
In this portion of the product, despite closing any doors which form a barrier between the tap and the outside environment, the quantity of bacteria increases rapidly, and if the deliveries are not very frequent, this quantity of bacteria tends to contaminate the product inside the tap as well. In this case the user is forced to throw away the first portion of the delivery in order to avoid the risk of giving the consumer a contaminated product.